Bed and platen printer with spring biased platen control lever

ABSTRACT

A DEVICE FOR CONTROLLING THE OPERATION OF A PLANAR PLATEN IN A PRINTING MACHINE AND MORE PARTICULARLY FOR REDUCING THE OPERATING LOAD REQUIREMENT FOR THE PRESSURE PRINTING OF A STUFFED ENVELOPED, OR THE LIKE, REGARDLESS OF ITS THICKNESS.

H. K. WAIBEL Sept; 21, 1971 BED AND-PLATEN PRINTER WITH SPRING BIASED PLATEN CONTROL LEVER Filed Nov. 3, 1969 INVIZNTOR.

United States Patent 3 606,837 BED AND PLATEN PRINTER WITH SPRING BIASED PLATEN CONTROL LEVER Helmut K. Waibel, Vista, N.Y., assignor 'to The Singer Company, New York, N.Y. Filed Nov. 3, 1969, Ser. No. 873,241 Int. Cl. B41f 1/06 US. Cl. 101-316 2 Claims ABSTRACT OF THE DISCLOSURE A device for controlling the operation of a planar platen in a printing machine and more particularly for reducing the operating load requirement for the pressure printing of a stutfed envelope, or the like, regardless of its thickness.

BACKGROUND OF THE INVENTION Field of the invention The invention relates to printing apparatus such as a postage meter, having a stationary indicium, or printing plate, and a fiat surfaced platen which is moved relative to the printing plate. As the platen moves toward the printing plate, a stuffed envelope is pressed against the plate to receive an impression therefrom.

Description of prior art In the prior art devices, a pair of members are rockable about a common shaft during an imprinting stroke, one is a driven member supporting the platen and the other is the driving member. As the driving member is rocked by the angular rotation of a cam, an interconnecting coil spring is effective to rock the driven member moving the platen and a stuffed envelope carried thereby into contact with the printing die plate. Upon completing the imprinting stroke, the coil spring is compressed to cause an impression to be made on the envelope. The operating stroke of the driven member must be sufiiciently long to compress the spring enough to develop adequate imprinting force for the thinnest envelope. For greater thicknesses of stutfed envelopes, the compression of the spring begins sooner in the operating stroke and continues for the full stroke. Thus, as the thickness of the envelopes increases, the greater the imprinting force to be applied and the greater the energy required to operate the machine, whether it be manually controlled or motor-driven.

With the use of the present invention, the energy required to cause an impression of an indicium to be made on mail matter, be it the thinnest or the thickest envelope, is considerably reduced. To this end, the driving member is pivotally connected to the driven member and a reduced pressure angle of the cam is provided With a reduction in the spring deflection. Thus, an operator experiences less fatigue or, if the machine is motor-driven, a much smaller motor may be utilized.

SUMMARY OF THE INVENTION This invention relates to a printing machine having a stationary printing die and a platen for moving an article to be printed into contact with the printing die. A member supports the platen and controls the movement of the platen, relative to the printing die. A means is connected to the supporting member and is actuated by an actuating means controlling a printing cycle of operation. During a printing cycle of operation, the actuating means operates the connected means and a yieldable member supported between the connected means and supporting means effects movement of the platen to engage an article to be printed with the printing die. Following the initial contact of the article with the printing die and the completion of the printing cycle, the yieldable member applies imprinting pressure to effect a printed impression.

Patented Sept. 21, 1971 p CC DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION The invention is preferably shown as being embodied in a postage metering machine of the type described in the copending application of Maynard E. Anderson et al., Ser. No. 686,613, filed Nov. 29, 1967, and includes a base 10 to which is secured a pair of spaced parallel frame members 11 and 12. Secured in place between frame members 11 and 12 is an indicium, or printing die plate, 15, the printing surface 16 of which is disposed in a horizontal plane. The printing plate 15 includes the postal indicium, the postage value printing die members and the town circle die and date printing members for the printing of postage impressions upon envelopes and other mail matter.

Also secured in the framework of the machine, between frame plates 11 and 12, is an envelope supporting table 17, the top surface of which is spaced below and is parallel with, the horizontally disposed surface 16 of the printing die plate 15. Within the top surface of the table 17 is a rectangular opening 18, slightly larger than, and in registry with, the printing die surface 16. As an envelope E to be printed is placed upon the table 17, as seen in FIG. 2, means are actuated to move the envelope into printing contact with the printing die surface 16, whereupon the postage impression is caused to be made.

For this purpose, a pair of platens, generally indicated at 19 and 20, are normally disposed in spaced relationship to the printing surface 1 6 of plate 15 and directly beneath the aperture 18 in the supporting table 17. Generally, each of the platens 19 and 20 comprises a flexible pad 21 and 22, respectively (FIG. 1). Each of the pads 21 and 22 is supported in a carrier frame similar to carrier frame 23 in FIGS. 2 and 3. The top surfaces of the pads 21 and 22 are coplanar with the pad 21, being effective upon movement toward the printing plate 15, to cause an impression of a slogan to be made on an envelope E. At the same time, the pad 22 presses the envelope E into contact with the postal indicium area of the printing plate 15, including the postage value, town circle and date, to complete the postage impression.

At its lower end, each of the carrier frames 23 is bifurcated to receive the end portion of respective arms 24 and 25, having a pivotal connection therewith by means of similar pins, such as pin 26 shown in FIGS. 2 and 3. At the one end, the arms 24 and 25 are maintained in a parallel relationship and at their other end, are laterally offset inwardly and are carried by respective hubs 30 and 31, rockably supported on a shaft 32 supported in frame members 11 and 12. The arms 24 and 25 are rocked clockwise from the inactive position shown in FIG. 2 moving the platens 19 and 2.0 upwardly to move an envelope E into printing contact with the surface 16 of the die plate 15.

Each of the platens 1.9 and 20 is guided in its upward movement to maintain the respective pads 21 and 22 horizontal and in a parallel relationship to the printing surface 16 of the die plate 15. For this purpose, a substantially U-shaped guide bracket 33 is flexibly supported by means of screws 34 on a boss cast, or otherwise formed,

on the base 10. The pair of flanges of the U-shaped bracket 33, similar to flange 35, extend upwardly in spaced parallel relationship and are engaged in the bifurcated lower extended portion of the corresponding carrier frames 23. Each of the flanges 35 is provided with a slot, identical to the slot 36 in the flange 35, as seen in FIG. 3. A pin is supported in each of; the lower extended portions of the carrier frames 23, similar to the pin 37, shown in FIG. 3, spanning the bifurcation in each of the carrier frames and adapted to engage in the slot 36 of the corresponding upwardly extended flange 35 of the U-shaped bracket 33. For a more complete description of the platen guide mechanism, reference is to be had to the copending application of Helmut K. Waibel, Ser. No. 831,327, filed June 9, 1969.

In order to control the rocking movement of the arms 24 and 25 and the movement of the respective platens 19 and 20 to printing position, a pair of L-shaped lever arms 40 and 41 are provided. At their one end, lever arms 40, 41 are secured on the respective ends of; a sleeve 42, pivotally supported on a shaft 43 secured at its respective ends in arms 24 and 25 between and axially parallel to shaft 32 and platen support pins 26. At the other end, the arms and 41 are maintained in parallel spatial relationship by means of a shaft 45 secured at its ends in the arms 40 and 41 and serving to support a roller 44. The inner surface of the laterally inwardly offset ends of the arms 24 and 25 is contiguous with the outer surface of the respective lever arms 40' and 41-. And the parallel spaced relationship of the arms 24 and 25 is maintained by means of a pair of spacers 46 and 47 carried by shaft 43 and disposed between arms 24 and 40 and arms 25 and 41, respectively.

Roller 44 is adapted for engagement with a cam 48 secured on a drive shaft 49, journalled in frame members 11 and 12. The roller 44 is normally maintained in engagement with the cam 48 by a spring 50, supported at its one end in a clip 51 carried at one end of the roller shaft 45 and at its other end, the spring is supported on a pin 52 secured on frame member 12. At its one end, adjacent frame member 12, drive shaft 49 carries a crank arm (not shown) secured thereon and adaptable, upon a predetermined angular movement thereof, to rock the cam 48 moving platens 19 and :20 upwardly toward the indicium printing plate 15.

Upon the counter-clockwise rocking movement of cam 48 (lFIG. 2) for a printing cycle of postage meter operation, lever arms 40, 41 and platen arms 24, 25 are adapted to rock as a unit, moving the platens 19 and 20 upwardly to cause envelope E to contact the printing surface 16 of printing die plate 15. Following the contact of the envelope E with the printing surface 16, and upon completing the rocking movement of the cam 48, printing pressure is applied to cause the postage impression to be made on the envelope E. In order to effect the unitary rocking movement of lever arms 40, 41 and platen arms 24, 25, a relatively strong compression spring 56 is provided.-At its one end, the spring 56 engages a pin projecting outwardly from a flat, chordal surface of a shaft 57, the reduced diametral ends of which are engaged in suitable notches in a depending portion, or ear, of each of platen control arms 2.4 and 25. At its other end, spring 56 encircles a pin projecting outwardly from a T-shaped bar 58 engaged in identical notches 59 provided in the foot portion of; each of L-shaped lever arms 40 and 41.

Normally, spring 56 is under suificient compression to maintain the top edge of each of lever arms 40 and 41 in contact with shaft 32. Thus, during the initial counterclockwise rocking movement of the cam 48 (as seen in FIG. 3), the arms 40, 41 and platen arms 24, '25 rock together about shaft 32. As these arms rock together, the platents 19 and 20 are moved upwardly through the aperture 18 in the envelope support table 17 to lift the envelope E into contact with the indicium printing surface 16 of the printing die plate 15. In order to effect the printing of the postage impression on an envelope E having the thickness shown in FIG. 3, cam 48 continues to be rocked counter-clockwise following the initial contact of the envelope with the printing die surface 16. Upon movement of the cam 48 from the full-line position shown in FIG. 3 to the dash line position shown, lever arms 40,41 are rocked slightly independently of the platen control arms 24 and .25 to the position indicated by phantom line in FIG. 3. With this additional movement of the lever arms 40, 41 spring 56 becomes compressed to effect printing pressure of the envelope E against the printing surface 16 of the die plate 15 to produce a well defined postage impression. Upon completion of the printing operation and restoration of the crank arm and cam 48 to the normally inactive position shown in FIG. 2, spring 50 is effective to return the platens 19* and 20 to their normally inactive position.

Because of the low pressure angle of the cam 48 and the pivotal connection of the lever arms 40, 41 on shaft 43, carried by the platen arms 24, 25, a minimal force is required to rock cam 48 through a full imprinting cycle of operation regardless of the thickness of the letter receiving the postage impression. During the initial portion of the printing cycle of operation, the roller 44 moves in an are about shaft 32 with a given pressure angle of the cam 48. However, following the initial contact of the envelope with the printing die surface, the roller 44 moves in an are about pivot shaft 43 and at a reduced pressure angle to eflect imprinting pressure on the envelope.

What is claimed is:

1. In a printing machine,

a framework,

a stationary printing die plate in said framework,

a platen member for effecting printing contact of an article with said die plate,

a shaft supported in said framework,

a plurality of spaced parallel arms each rockably mounted on said shaft,

pivotal means for supporting said platen member on each of said arms for movement of said platen member relative to said die plate upon rocking of said arms,

a pair of similar spaced parallel levers having one end rockably connected to said arms for movement of said levers in one direction, the connection of said levers on said arms being intermediate said shaft and said pivotal supporting means,

said levers normally abutting said shaft at a position intermediate the ends of said lever to limit the rocking movement of said lever in the other direction,

a roller carried by said levers at an end opposite said one end,

a cam engaging said roller for actuation of said levers to control a printing cycle of operation, and

a yieldable means supported between said levers and said arms for normally maintaining said levers in engagement with said shaft to enable the rocking of said levers about the axis of said shaft upon operation of said cam and to enable a concomitant rocking of said arms by said levers to move an artic to be printed into contact with said die plate during the initial portion of a printing cycle of operation,

said cam being effective during the remainder of the printing cycle of operation to cause rocking of said levers in said one direction on said arms thereby enabling said yieldable means to apply printing pressure for the taking of an impression from said die plate.

2. In a device of the character described in claim 1 wherein said yieldable means is a compression spring normally biasing said levers into engagement with said shaft and effective during a predetermined angular rotation of said cam to enable the movement of said platen member for the engagement of an article to be printed with said die plate, said compression spring being compressible cam.

References Cited UNITED STATES PATENTS Campbell 26775 Moody 101287X Jones 172500X Stahl 101 287UX Durrant et a1. 101-298 6 5/1938 Gustavson 292373UX 1/1958 Larrabee 101-287 4/1968 Harrison 101-316 FOREIGN PATENTS 11/1968 Great Britain 101316 WILLIAM B. PENN, Primary Examiner E. M. COVEN, Assistant Examiner US. Cl. X.R. 

